Recent years have seen rapid proliferation of Internet and mobile communication services. Communications over the Internet are carried out by transmitting IP packets according to the de facto standard IP protocol (Internet Protocol, RFC 791). To each equipment connected to the Internet, an IP address unique in itself is assigned for identification thereof, and IP packet routing is performed using each unique IP address.
Upon receipt of an IP packet, a node apparatus checks a destination IP address contained in a header of the IP packet. If a terminal having the destination IP address is not found in the node apparatus, the IP packet is transferred to a node adjacent thereto using a routing table which provides correspondence relationships of IP addresses and adjacent nodes.
In the late 1970s when the currently used version of the Internet Protocol (IPv4) address space was designed, it was unimaginable that it could be outdated. However, due to changes in technology and an allocation practice that did not anticipate the recent explosion of hosts on the Internet, the IPv4 address space was consumed to the point that by 1992 it was clear a replacement would be necessary.
Due to recent concerns over the impending depletion of the current pool of Internet addresses and the desire to provide additional functionality for modern devices, an upgrade of IPv4 is in the process of standardization. This new version, called IP Version 6 (IPv6) resolves unanticipated IPv4 design issues and is poised to take the Internet into the 21st Century. Internet Protocol version 6 (IPv6) is the next generation of network layer protocols for the Internet and represents the future of networking.
The most obvious distinguishing feature of IPv6 is its use of much larger addresses. The size of an address in IPv6 is 128 bits, which is four times larger than an address in IPv4 (32-bit). This has a dramatic affect upon the number of possible addresses. See Table 1.
TABLE 1 32-bit4,294,967,296 addresses128-bit3.4 × 1038 addresses
IPv4 addresses are represented in a “dotted-decimal” format, 32-bit addresses divided along 8-bit boundaries. IPv6 addresses are represented in dotted-decimal format, 128-bit addresses divided along 16-bit boundaries. The more customary format of the IP address is then generated by converting each bit set into its decimal (IPv4) or hexadecimal (IPv6) equivalent. For example: 192.168.100.12 and 21DA:00D3:0000:2F3B:02AA:00FF:FE28:9C5A.
Current gateway application programs (i.e. security programs, network analyzers, etc.) only have functionality capable of dealing with IPv4 addresses. However, most underlying operating systems, (i.e. Windows 2000 Server, Linux/Unix, etc.) are capable of handling IPv6 addresses with some minor configuration and/or installation.
There is thus a need for a technique to facilitate the processing of data communicated with IPv6 using an application program.